The objective of this research training program is to apply social network methods to understand the role and influence of the family network system on the communication of risk information and engagement in risk-reducing behaviors in families at risk of type 2 diabetes (T2D) based on family health history (FHH). Although lifestyle factors can help prevent or delay the onset of T2D, the public health burden of T2D continues to rise. FHH is a risk factor for T2D and can help identify those at increased risk who may benefit from targeted interventions. The family network system may be an ideal context to develop such interventions, since family members share behaviors, environmental influences, and, if biologically related, genes. Family-based interventions aimed at increased understanding of FHH and promoting adoption of risk-reducing behaviors among those at increased risk of T2D may be particularly effective. However, the role of social influence on risk-reducing behaviors within families at risk of T2D has not been examined. The proposed research will fill this gap in the literature. This is a one year mixed-methods study involving the collection of qualitative data through telephone interviews and quantitative survey data collected either online or through telephone interviews depending on participants'preference. Quantitative survey data will be collected using Cyber-Infrastructure for Inquiring Knowledge Networks on the Web (C-IKNOW), a free web-based software tool designed to collect and analyze social network data. Measures that will be assessed include participant information (demographics, health behaviors, and personal health information), perceived FHH of T2D and related conditions, and network assessment via the telephone interview and/or online survey (enumeration of family members including social kin, communication of FHH-based risk information, encouragement and co-engagement related to lifestyle behaviors, and family functioning characteristics such as cohesion, conflict, expressiveness). Social network methods will be used to investigate whether patterns of communication regarding T2D relevant FHH information and behavioral encouragement are associated with health behaviors that reduce T2D risk in at-risk families. Findings from this study could contribute to the development of novel interventions that capitalize on established patterns of social influence within at-risk families. The scientific disciplines represented by the proposed mentor include quantitative psychology, statistics, and social network methodology. The scientific disciplines represented by the candidate include genetic counseling, public health genomics (with an emphasis on social and behavioral science), and applied epidemiology. PUBLIC HEALTH RELEVANCE: Social network methods will be used to identify family members who are central to the dissemination of family risk information and influential in motivating engagement in risk-reducing behaviors among family members at risk of type 2 diabetes based on family history. The proposed research training program has relevance to public health because employing influential family members identified through social network methods in intervention efforts may be particularly effective in achieving sustainable behavior change.